Various types of automatic packaging machines are known and used for assembling paperboard and/or cardboard packages from precut box blanks. These packages can be used to hold a wide variety of items, ranging from chewing gum to candy to office supplies: U.S. Pat. Nos. 4,578,929; 4,548,593; 4,716,714; 4,829,751; 4,856,566; 4,982,556; 5,010,929; 5,072,573; 5,144,790; and 6,195,959 are examples of packaging machines which may be used to load small items into different types of packages.
Conventional automatic packing machines include a conveyor, usually an endless link chain conveyor, which travels through or past a number of work stations extending between a magazine containing package blanks and a product discharge end. Usually, the package blanks are a stack of die cut paperboard or cardboard blanks which are picked up one-at-a-time by vacuum cups and then put into package-forming mandrels carried by the conveyor. Panels and flaps on the bottom of the blank are folded by a series of plows and sealed in order to close the package. A pre-determined amount of product is then placed in the package. Next, panels and flaps forming a top of the package are folded and sealed. Then the package is discharged onto any suitable conveyor, into a shipping carton, or to another device for receiving the completed product containing packaging.
Conventionally, a plow is a strip of metal, or the like, extending along a length of the conveyor and in a location where the panels and flaps are to be folded. First, panels and flaps forming the bottom of the package encounter the plows and then are folded as the conveyor carries the package past the plow. Then, a pre-determined amount of product is placed in the package. Next, panels and flaps forming a top of the package are folded and sealed in a similar manner. Depending upon product packaging needs, the package may or may not be wrapped in a transparent film which is sealed. Finally, the package is discharged onto any suitable conveyor, into a shipping box or another suitable device for receiving the product containing package.
Often, the product presents special considerations which require the packaging machine to perform unique functions as the package is formed and filled. These functions may be performed by special parts which are attached to or positioned near the conveyor. Many examples of such special parts are shown and described in the above-cited patents.
One type of conventional package which is often used for candy and mints is commonly referred to as a “flip-top” box or package. Such a package is made from a single, unitary, die cut blank of thin cardboard stock. A flip-top package has a bottom section which is in the form of a rectangular parallelepiped. The top of the package is in the form of a hood connected to the bottom along a crease line which acts as a hinge. The hood moves away from or over the top of the package in order to open or close it. It is necessary for the packaging machine to first form the blank into the package, then count a specific number of small items, such as candy coated chewing gum, next deposit them in the package, and finally close and seal the package. One such “flip-top” package is shown in prior art FIG. 1.
Prior art FIG. 2 shows one type of example automatic packaging machine for assembling the type of “flip-top” package of FIG. 1. This machine is described in detail in U.S. Pat. No. 6,195,959 and is incorporated herein by reference. This system uses a two-part mandrel which is joined by a single hinge. One of the two hinged parts includes a roller thereon for following a cam track having a quarter turn spiral therein. As the roller follows the spiral causing one hinged part to move through a quarter turn, the flip-top is folded over and formed.
In the conventional “flip-top” package shown in FIG. 1, the hinge of the flip-top joins the flip-top to the entire width of the (longer) major plane of the package. As a result, when the flip-top is opened, the entire top area of the package is exposed. Recently, however, a new type of “flip-top” package has been developed. This new package is shown at 98 in FIG. 3. The package 98, like the conventional package of FIG. 1, includes a flip-top 101 hingedly connected to an upper portion 103 of the package. Unlike the conventional package, however, the flip-top's hinge 105 runs along the (shorter) minor plane of the package, substantially perpendicular to the hinge line of the conventional “flip top” package. Furthermore, the hinge 105 runs across the middle of the package top, unlike the conventional package. As a result, the new package 98 has a hole 108 within a side panel 106 of the package 98 instead of having the top entirely open when the flip-top 101 is “flipped open.”
This new type of “partial flip-top” package requires several more distinct flaps than the previous packages, which adds a significant amount of complexity to any machine for assembling and filling the packages. In particular, problems arise because the mandrels used in the conventional assembly devices are not properly aligned to fold down the top panels of the package blank to form the flip-top of the package. Several additional steps are therefore required to complete the assembly process. This results in increased complexity and assembly time, diminishing the assembly machine's efficiency.